svn commit: r215060 - in stable/8/sys: amd64/amd64 conf i386/i386 x86/x86

Alexander Motin mav at FreeBSD.org
Tue Nov 9 22:03:39 UTC 2010


Author: mav
Date: Tue Nov  9 22:03:39 2010
New Revision: 215060
URL: http://svn.freebsd.org/changeset/base/215060

Log:
  MFC r208922 by jhb:
  Move the MD support for PCI message signalled interrupts to the x86 tree
  as it is identical for i386 and amd64.

Added:
  stable/8/sys/x86/x86/msi.c
     - copied unchanged from r208922, head/sys/x86/x86/msi.c
Deleted:
  stable/8/sys/amd64/amd64/msi.c
  stable/8/sys/i386/i386/msi.c
Modified:
  stable/8/sys/conf/files.amd64
  stable/8/sys/conf/files.i386
  stable/8/sys/conf/files.pc98
Directory Properties:
  stable/8/sys/   (props changed)
  stable/8/sys/amd64/include/xen/   (props changed)
  stable/8/sys/cddl/contrib/opensolaris/   (props changed)
  stable/8/sys/contrib/dev/acpica/   (props changed)
  stable/8/sys/contrib/pf/   (props changed)
  stable/8/sys/dev/xen/xenpci/   (props changed)

Modified: stable/8/sys/conf/files.amd64
==============================================================================
--- stable/8/sys/conf/files.amd64	Tue Nov  9 21:18:32 2010	(r215059)
+++ stable/8/sys/conf/files.amd64	Tue Nov  9 22:03:39 2010	(r215060)
@@ -123,7 +123,6 @@ amd64/amd64/minidump_machdep.c	standard
 amd64/amd64/mp_machdep.c	optional	smp
 amd64/amd64/mp_watchdog.c	optional	mp_watchdog smp
 amd64/amd64/mpboot.S		optional	smp
-amd64/amd64/msi.c		optional	pci
 amd64/amd64/nexus.c		standard
 amd64/amd64/pmap.c		standard
 amd64/amd64/prof_machdep.c	optional	profiling-routine
@@ -319,3 +318,4 @@ x86/x86/dump_machdep.c		standard
 x86/x86/mca.c			standard
 x86/x86/mptable.c		optional	mptable
 x86/x86/mptable_pci.c		optional	mptable pci
+x86/x86/msi.c			optional	pci

Modified: stable/8/sys/conf/files.i386
==============================================================================
--- stable/8/sys/conf/files.i386	Tue Nov  9 21:18:32 2010	(r215059)
+++ stable/8/sys/conf/files.i386	Tue Nov  9 22:03:39 2010	(r215060)
@@ -289,7 +289,6 @@ i386/xen/mp_machdep.c		optional xen smp
 i386/i386/mp_watchdog.c		optional mp_watchdog smp
 i386/i386/mpboot.s		optional smp native
 i386/xen/mptable.c		optional apic xen
-i386/i386/msi.c			optional apic pci
 i386/i386/nexus.c		standard
 i386/i386/perfmon.c		optional perfmon
 i386/i386/pmap.c		optional native
@@ -394,3 +393,4 @@ x86/x86/dump_machdep.c		standard
 x86/x86/mca.c			standard
 x86/x86/mptable.c		optional apic native
 x86/x86/mptable_pci.c		optional apic pci
+x86/x86/msi.c			optional apic pci

Modified: stable/8/sys/conf/files.pc98
==============================================================================
--- stable/8/sys/conf/files.pc98	Tue Nov  9 21:18:32 2010	(r215059)
+++ stable/8/sys/conf/files.pc98	Tue Nov  9 22:03:39 2010	(r215060)
@@ -158,7 +158,6 @@ i386/i386/mp_clock.c		optional smp
 i386/i386/mp_machdep.c		optional smp
 i386/i386/mp_watchdog.c		optional mp_watchdog smp
 i386/i386/mpboot.s		optional smp
-i386/i386/msi.c			optional apic pci
 i386/i386/nexus.c		standard
 i386/i386/perfmon.c		optional perfmon
 i386/i386/pmap.c		standard
@@ -258,3 +257,4 @@ x86/x86/dump_machdep.c		standard
 x86/x86/mca.c			standard
 x86/x86/mptable.c		optional apic
 x86/x86/mptable_pci.c		optional apic pci
+x86/x86/msi.c			optional apic pci

Copied: stable/8/sys/x86/x86/msi.c (from r208922, head/sys/x86/x86/msi.c)
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ stable/8/sys/x86/x86/msi.c	Tue Nov  9 22:03:39 2010	(r215060, copy of r208922, head/sys/x86/x86/msi.c)
@@ -0,0 +1,602 @@
+/*-
+ * Copyright (c) 2006 Yahoo!, Inc.
+ * All rights reserved.
+ * Written by: John Baldwin <jhb at FreeBSD.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * Support for PCI Message Signalled Interrupts (MSI).  MSI interrupts on
+ * x86 are basically APIC messages that the northbridge delivers directly
+ * to the local APICs as if they had come from an I/O APIC.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/bus.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/mutex.h>
+#include <sys/sx.h>
+#include <sys/systm.h>
+#include <machine/apicreg.h>
+#include <machine/cputypes.h>
+#include <machine/md_var.h>
+#include <machine/frame.h>
+#include <machine/intr_machdep.h>
+#include <machine/apicvar.h>
+#include <machine/specialreg.h>
+#include <dev/pci/pcivar.h>
+
+/* Fields in address for Intel MSI messages. */
+#define	MSI_INTEL_ADDR_DEST		0x000ff000
+#define	MSI_INTEL_ADDR_RH		0x00000008
+# define MSI_INTEL_ADDR_RH_ON		0x00000008
+# define MSI_INTEL_ADDR_RH_OFF		0x00000000
+#define	MSI_INTEL_ADDR_DM		0x00000004
+# define MSI_INTEL_ADDR_DM_PHYSICAL	0x00000000
+# define MSI_INTEL_ADDR_DM_LOGICAL	0x00000004
+
+/* Fields in data for Intel MSI messages. */
+#define	MSI_INTEL_DATA_TRGRMOD		IOART_TRGRMOD	/* Trigger mode. */
+# define MSI_INTEL_DATA_TRGREDG		IOART_TRGREDG
+# define MSI_INTEL_DATA_TRGRLVL		IOART_TRGRLVL
+#define	MSI_INTEL_DATA_LEVEL		0x00004000	/* Polarity. */
+# define MSI_INTEL_DATA_DEASSERT	0x00000000
+# define MSI_INTEL_DATA_ASSERT		0x00004000
+#define	MSI_INTEL_DATA_DELMOD		IOART_DELMOD	/* Delivery mode. */
+# define MSI_INTEL_DATA_DELFIXED	IOART_DELFIXED
+# define MSI_INTEL_DATA_DELLOPRI	IOART_DELLOPRI
+# define MSI_INTEL_DATA_DELSMI		IOART_DELSMI
+# define MSI_INTEL_DATA_DELNMI		IOART_DELNMI
+# define MSI_INTEL_DATA_DELINIT		IOART_DELINIT
+# define MSI_INTEL_DATA_DELEXINT	IOART_DELEXINT
+#define	MSI_INTEL_DATA_INTVEC		IOART_INTVEC	/* Interrupt vector. */
+
+/*
+ * Build Intel MSI message and data values from a source.  AMD64 systems
+ * seem to be compatible, so we use the same function for both.
+ */
+#define	INTEL_ADDR(msi)							\
+	(MSI_INTEL_ADDR_BASE | (msi)->msi_cpu << 12 |			\
+	    MSI_INTEL_ADDR_RH_OFF | MSI_INTEL_ADDR_DM_PHYSICAL)
+#define	INTEL_DATA(msi)							\
+	(MSI_INTEL_DATA_TRGREDG | MSI_INTEL_DATA_DELFIXED | (msi)->msi_vector)
+
+static MALLOC_DEFINE(M_MSI, "msi", "PCI MSI");
+
+/*
+ * MSI sources are bunched into groups.  This is because MSI forces
+ * all of the messages to share the address and data registers and
+ * thus certain properties (such as the local APIC ID target on x86).
+ * Each group has a 'first' source that contains information global to
+ * the group.  These fields are marked with (g) below.
+ *
+ * Note that local APIC ID is kind of special.  Each message will be
+ * assigned an ID by the system; however, a group will use the ID from
+ * the first message.
+ *
+ * For MSI-X, each message is isolated.
+ */
+struct msi_intsrc {
+	struct intsrc msi_intsrc;
+	device_t msi_dev;		/* Owning device. (g) */
+	struct msi_intsrc *msi_first;	/* First source in group. */
+	u_int msi_irq;			/* IRQ cookie. */
+	u_int msi_msix;			/* MSI-X message. */
+	u_int msi_vector:8;		/* IDT vector. */
+	u_int msi_cpu:8;		/* Local APIC ID. (g) */
+	u_int msi_count:8;		/* Messages in this group. (g) */
+	u_int msi_maxcount:8;		/* Alignment for this group. (g) */
+	int *msi_irqs;			/* Group's IRQ list. (g) */
+};
+
+static void	msi_create_source(void);
+static void	msi_enable_source(struct intsrc *isrc);
+static void	msi_disable_source(struct intsrc *isrc, int eoi);
+static void	msi_eoi_source(struct intsrc *isrc);
+static void	msi_enable_intr(struct intsrc *isrc);
+static void	msi_disable_intr(struct intsrc *isrc);
+static int	msi_vector(struct intsrc *isrc);
+static int	msi_source_pending(struct intsrc *isrc);
+static int	msi_config_intr(struct intsrc *isrc, enum intr_trigger trig,
+		    enum intr_polarity pol);
+static int	msi_assign_cpu(struct intsrc *isrc, u_int apic_id);
+
+struct pic msi_pic = { msi_enable_source, msi_disable_source, msi_eoi_source,
+		       msi_enable_intr, msi_disable_intr, msi_vector,
+		       msi_source_pending, NULL, NULL, msi_config_intr,
+		       msi_assign_cpu };
+
+static int msi_enabled;
+static int msi_last_irq;
+static struct mtx msi_lock;
+
+static void
+msi_enable_source(struct intsrc *isrc)
+{
+}
+
+static void
+msi_disable_source(struct intsrc *isrc, int eoi)
+{
+
+	if (eoi == PIC_EOI)
+		lapic_eoi();
+}
+
+static void
+msi_eoi_source(struct intsrc *isrc)
+{
+
+	lapic_eoi();
+}
+
+static void
+msi_enable_intr(struct intsrc *isrc)
+{
+	struct msi_intsrc *msi = (struct msi_intsrc *)isrc;
+
+	apic_enable_vector(msi->msi_cpu, msi->msi_vector);
+}
+
+static void
+msi_disable_intr(struct intsrc *isrc)
+{
+	struct msi_intsrc *msi = (struct msi_intsrc *)isrc;
+
+	apic_disable_vector(msi->msi_cpu, msi->msi_vector);
+}
+
+static int
+msi_vector(struct intsrc *isrc)
+{
+	struct msi_intsrc *msi = (struct msi_intsrc *)isrc;
+
+	return (msi->msi_irq);
+}
+
+static int
+msi_source_pending(struct intsrc *isrc)
+{
+
+	return (0);
+}
+
+static int
+msi_config_intr(struct intsrc *isrc, enum intr_trigger trig,
+    enum intr_polarity pol)
+{
+
+	return (ENODEV);
+}
+
+static int
+msi_assign_cpu(struct intsrc *isrc, u_int apic_id)
+{
+	struct msi_intsrc *sib, *msi = (struct msi_intsrc *)isrc;
+	int old_vector;
+	u_int old_id;
+	int i, vector;
+
+	/*
+	 * Only allow CPUs to be assigned to the first message for an
+	 * MSI group.
+	 */
+	if (msi->msi_first != msi)
+		return (EINVAL);
+
+	/* Store information to free existing irq. */
+	old_vector = msi->msi_vector;
+	old_id = msi->msi_cpu;
+	if (old_id == apic_id)
+		return (0);
+
+	/* Allocate IDT vectors on this cpu. */
+	if (msi->msi_count > 1) {
+		KASSERT(msi->msi_msix == 0, ("MSI-X message group"));
+		vector = apic_alloc_vectors(apic_id, msi->msi_irqs,
+		    msi->msi_count, msi->msi_maxcount);
+	} else
+		vector = apic_alloc_vector(apic_id, msi->msi_irq);
+	if (vector == 0)
+		return (ENOSPC);
+
+	msi->msi_cpu = apic_id;
+	msi->msi_vector = vector;
+	if (msi->msi_intsrc.is_handlers > 0)
+		apic_enable_vector(msi->msi_cpu, msi->msi_vector);
+	if (bootverbose)
+		printf("msi: Assigning %s IRQ %d to local APIC %u vector %u\n",
+		    msi->msi_msix ? "MSI-X" : "MSI", msi->msi_irq,
+		    msi->msi_cpu, msi->msi_vector);
+	for (i = 1; i < msi->msi_count; i++) {
+		sib = (struct msi_intsrc *)intr_lookup_source(msi->msi_irqs[i]);
+		sib->msi_cpu = apic_id;
+		sib->msi_vector = vector + i;
+		if (sib->msi_intsrc.is_handlers > 0)
+			apic_enable_vector(sib->msi_cpu, sib->msi_vector);
+		if (bootverbose)
+			printf(
+		    "msi: Assigning MSI IRQ %d to local APIC %u vector %u\n",
+			    sib->msi_irq, sib->msi_cpu, sib->msi_vector);
+	}
+	pci_remap_msi_irq(msi->msi_dev, msi->msi_irq);
+
+	/*
+	 * Free the old vector after the new one is established.  This is done
+	 * to prevent races where we could miss an interrupt.
+	 */
+	if (msi->msi_intsrc.is_handlers > 0)
+		apic_disable_vector(old_id, old_vector);
+	apic_free_vector(old_id, old_vector, msi->msi_irq);
+	for (i = 1; i < msi->msi_count; i++) {
+		sib = (struct msi_intsrc *)intr_lookup_source(msi->msi_irqs[i]);
+		if (sib->msi_intsrc.is_handlers > 0)
+			apic_disable_vector(old_id, old_vector + i);
+		apic_free_vector(old_id, old_vector + i, msi->msi_irqs[i]);
+	}
+	return (0);
+}
+
+void
+msi_init(void)
+{
+
+	/* Check if we have a supported CPU. */
+	switch (cpu_vendor_id) {
+	case CPU_VENDOR_INTEL:
+	case CPU_VENDOR_AMD:
+		break;
+	case CPU_VENDOR_CENTAUR:
+		if (CPUID_TO_FAMILY(cpu_id) == 0x6 &&
+		    CPUID_TO_MODEL(cpu_id) >= 0xf)
+			break;
+		/* FALLTHROUGH */
+	default:
+		return;
+	}
+
+	msi_enabled = 1;
+	intr_register_pic(&msi_pic);
+	mtx_init(&msi_lock, "msi", NULL, MTX_DEF);
+}
+
+static void
+msi_create_source(void)
+{
+	struct msi_intsrc *msi;
+	u_int irq;
+
+	mtx_lock(&msi_lock);
+	if (msi_last_irq >= NUM_MSI_INTS) {
+		mtx_unlock(&msi_lock);
+		return;
+	}
+	irq = msi_last_irq + FIRST_MSI_INT;
+	msi_last_irq++;
+	mtx_unlock(&msi_lock);
+
+	msi = malloc(sizeof(struct msi_intsrc), M_MSI, M_WAITOK | M_ZERO);
+	msi->msi_intsrc.is_pic = &msi_pic;
+	msi->msi_irq = irq;
+	intr_register_source(&msi->msi_intsrc);
+	nexus_add_irq(irq);
+}
+
+/*
+ * Try to allocate 'count' interrupt sources with contiguous IDT values.
+ */
+int
+msi_alloc(device_t dev, int count, int maxcount, int *irqs)
+{
+	struct msi_intsrc *msi, *fsrc;
+	u_int cpu;
+	int cnt, i, *mirqs, vector;
+
+	if (!msi_enabled)
+		return (ENXIO);
+
+	if (count > 1)
+		mirqs = malloc(count * sizeof(*mirqs), M_MSI, M_WAITOK);
+	else
+		mirqs = NULL;
+again:
+	mtx_lock(&msi_lock);
+
+	/* Try to find 'count' free IRQs. */
+	cnt = 0;
+	for (i = FIRST_MSI_INT; i < FIRST_MSI_INT + NUM_MSI_INTS; i++) {
+		msi = (struct msi_intsrc *)intr_lookup_source(i);
+
+		/* End of allocated sources, so break. */
+		if (msi == NULL)
+			break;
+
+		/* If this is a free one, save its IRQ in the array. */
+		if (msi->msi_dev == NULL) {
+			irqs[cnt] = i;
+			cnt++;
+			if (cnt == count)
+				break;
+		}
+	}
+
+	/* Do we need to create some new sources? */
+	if (cnt < count) {
+		/* If we would exceed the max, give up. */
+		if (i + (count - cnt) > FIRST_MSI_INT + NUM_MSI_INTS) {
+			mtx_unlock(&msi_lock);
+			free(mirqs, M_MSI);
+			return (ENXIO);
+		}
+		mtx_unlock(&msi_lock);
+
+		/* We need count - cnt more sources. */
+		while (cnt < count) {
+			msi_create_source();
+			cnt++;
+		}
+		goto again;
+	}
+
+	/* Ok, we now have the IRQs allocated. */
+	KASSERT(cnt == count, ("count mismatch"));
+
+	/* Allocate 'count' IDT vectors. */
+	cpu = intr_next_cpu();
+	vector = apic_alloc_vectors(cpu, irqs, count, maxcount);
+	if (vector == 0) {
+		mtx_unlock(&msi_lock);
+		free(mirqs, M_MSI);
+		return (ENOSPC);
+	}
+
+	/* Assign IDT vectors and make these messages owned by 'dev'. */
+	fsrc = (struct msi_intsrc *)intr_lookup_source(irqs[0]);
+	for (i = 0; i < count; i++) {
+		msi = (struct msi_intsrc *)intr_lookup_source(irqs[i]);
+		msi->msi_cpu = cpu;
+		msi->msi_dev = dev;
+		msi->msi_vector = vector + i;
+		if (bootverbose)
+			printf(
+		    "msi: routing MSI IRQ %d to local APIC %u vector %u\n",
+			    msi->msi_irq, msi->msi_cpu, msi->msi_vector);
+		msi->msi_first = fsrc;
+		KASSERT(msi->msi_intsrc.is_handlers == 0,
+		    ("dead MSI has handlers"));
+	}
+	fsrc->msi_count = count;
+	fsrc->msi_maxcount = maxcount;
+	if (count > 1)
+		bcopy(irqs, mirqs, count * sizeof(*mirqs));
+	fsrc->msi_irqs = mirqs;
+	mtx_unlock(&msi_lock);
+
+	return (0);
+}
+
+int
+msi_release(int *irqs, int count)
+{
+	struct msi_intsrc *msi, *first;
+	int i;
+
+	mtx_lock(&msi_lock);
+	first = (struct msi_intsrc *)intr_lookup_source(irqs[0]);
+	if (first == NULL) {
+		mtx_unlock(&msi_lock);
+		return (ENOENT);
+	}
+
+	/* Make sure this isn't an MSI-X message. */
+	if (first->msi_msix) {
+		mtx_unlock(&msi_lock);
+		return (EINVAL);
+	}
+
+	/* Make sure this message is allocated to a group. */
+	if (first->msi_first == NULL) {
+		mtx_unlock(&msi_lock);
+		return (ENXIO);
+	}
+
+	/*
+	 * Make sure this is the start of a group and that we are releasing
+	 * the entire group.
+	 */
+	if (first->msi_first != first || first->msi_count != count) {
+		mtx_unlock(&msi_lock);
+		return (EINVAL);
+	}
+	KASSERT(first->msi_dev != NULL, ("unowned group"));
+
+	/* Clear all the extra messages in the group. */
+	for (i = 1; i < count; i++) {
+		msi = (struct msi_intsrc *)intr_lookup_source(irqs[i]);
+		KASSERT(msi->msi_first == first, ("message not in group"));
+		KASSERT(msi->msi_dev == first->msi_dev, ("owner mismatch"));
+		msi->msi_first = NULL;
+		msi->msi_dev = NULL;
+		apic_free_vector(msi->msi_cpu, msi->msi_vector, msi->msi_irq);
+		msi->msi_vector = 0;
+	}
+
+	/* Clear out the first message. */
+	first->msi_first = NULL;
+	first->msi_dev = NULL;
+	apic_free_vector(first->msi_cpu, first->msi_vector, first->msi_irq);
+	first->msi_vector = 0;
+	first->msi_count = 0;
+	first->msi_maxcount = 0;
+	free(first->msi_irqs, M_MSI);
+	first->msi_irqs = NULL;
+
+	mtx_unlock(&msi_lock);
+	return (0);
+}
+
+int
+msi_map(int irq, uint64_t *addr, uint32_t *data)
+{
+	struct msi_intsrc *msi;
+
+	mtx_lock(&msi_lock);
+	msi = (struct msi_intsrc *)intr_lookup_source(irq);
+	if (msi == NULL) {
+		mtx_unlock(&msi_lock);
+		return (ENOENT);
+	}
+
+	/* Make sure this message is allocated to a device. */
+	if (msi->msi_dev == NULL) {
+		mtx_unlock(&msi_lock);
+		return (ENXIO);
+	}
+
+	/*
+	 * If this message isn't an MSI-X message, make sure it's part
+	 * of a group, and switch to the first message in the
+	 * group.
+	 */
+	if (!msi->msi_msix) {
+		if (msi->msi_first == NULL) {
+			mtx_unlock(&msi_lock);
+			return (ENXIO);
+		}
+		msi = msi->msi_first;
+	}
+
+	*addr = INTEL_ADDR(msi);
+	*data = INTEL_DATA(msi);
+	mtx_unlock(&msi_lock);
+	return (0);
+}
+
+int
+msix_alloc(device_t dev, int *irq)
+{
+	struct msi_intsrc *msi;
+	u_int cpu;
+	int i, vector;
+
+	if (!msi_enabled)
+		return (ENXIO);
+
+again:
+	mtx_lock(&msi_lock);
+
+	/* Find a free IRQ. */
+	for (i = FIRST_MSI_INT; i < FIRST_MSI_INT + NUM_MSI_INTS; i++) {
+		msi = (struct msi_intsrc *)intr_lookup_source(i);
+
+		/* End of allocated sources, so break. */
+		if (msi == NULL)
+			break;
+
+		/* Stop at the first free source. */
+		if (msi->msi_dev == NULL)
+			break;
+	}
+
+	/* Do we need to create a new source? */
+	if (msi == NULL) {
+		/* If we would exceed the max, give up. */
+		if (i + 1 > FIRST_MSI_INT + NUM_MSI_INTS) {
+			mtx_unlock(&msi_lock);
+			return (ENXIO);
+		}
+		mtx_unlock(&msi_lock);
+
+		/* Create a new source. */
+		msi_create_source();
+		goto again;
+	}
+
+	/* Allocate an IDT vector. */
+	cpu = intr_next_cpu();
+	vector = apic_alloc_vector(cpu, i);
+	if (vector == 0) {
+		mtx_unlock(&msi_lock);
+		return (ENOSPC);
+	}
+	if (bootverbose)
+		printf("msi: routing MSI-X IRQ %d to local APIC %u vector %u\n",
+		    msi->msi_irq, cpu, vector);
+
+	/* Setup source. */
+	msi->msi_cpu = cpu;
+	msi->msi_dev = dev;
+	msi->msi_first = msi;
+	msi->msi_vector = vector;
+	msi->msi_msix = 1;
+	msi->msi_count = 1;
+	msi->msi_maxcount = 1;
+	msi->msi_irqs = NULL;
+
+	KASSERT(msi->msi_intsrc.is_handlers == 0, ("dead MSI-X has handlers"));
+	mtx_unlock(&msi_lock);
+
+	*irq = i;
+	return (0);
+}
+
+int
+msix_release(int irq)
+{
+	struct msi_intsrc *msi;
+
+	mtx_lock(&msi_lock);
+	msi = (struct msi_intsrc *)intr_lookup_source(irq);
+	if (msi == NULL) {
+		mtx_unlock(&msi_lock);
+		return (ENOENT);
+	}
+
+	/* Make sure this is an MSI-X message. */
+	if (!msi->msi_msix) {
+		mtx_unlock(&msi_lock);
+		return (EINVAL);
+	}
+
+	KASSERT(msi->msi_dev != NULL, ("unowned message"));
+
+	/* Clear out the message. */
+	msi->msi_first = NULL;
+	msi->msi_dev = NULL;
+	apic_free_vector(msi->msi_cpu, msi->msi_vector, msi->msi_irq);
+	msi->msi_vector = 0;
+	msi->msi_msix = 0;
+	msi->msi_count = 0;
+	msi->msi_maxcount = 0;
+
+	mtx_unlock(&msi_lock);
+	return (0);
+}


More information about the svn-src-stable-8 mailing list